/*
 * Copyright 2017 Huawei Technologies Co., Ltd
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package io.servicecomb.tracing.zipkin;

import java.lang.invoke.MethodHandles;
import java.lang.reflect.Method;

import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.reflect.MethodSignature;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import brave.Tracing;
import io.servicecomb.tracing.Span;

@Aspect
class ZipkinSpanAspect {
  private static final Logger LOG = LoggerFactory.getLogger(MethodHandles.lookup().lookupClass());

  private final ZipkinTracingAdviser adviser;

  ZipkinSpanAspect(Tracing tracing) {
    this.adviser = new ZipkinTracingAdviser(tracing.tracer());
  }

  @Around("execution(@io.servicecomb.tracing.Span * *(..)) && @annotation(spanAnnotation)")
  public Object advise(ProceedingJoinPoint joinPoint, Span spanAnnotation) throws Throwable {
    String spanName = spanAnnotation.spanName();
    String callPath = spanAnnotation.callPath();
    Method method = ((MethodSignature) joinPoint.getSignature()).getMethod();
    LOG.debug("Generating zipkin span for method {}", method.toString());
    if ("".equals(spanName)) {
      spanName = method.getName();
    }
    if ("".equals(callPath)) {
      callPath = method.toString();
    }
    
    return adviser.invoke(spanName, callPath, joinPoint::proceed);
    
  }
}
